The new strategy is as follows. First, the `!` type is assigned
in two cases:
- a block with a diverging statement and no tail expression (e.g.,
`{return;}`);
- any expression with the type `!` is considered diverging.
Second, we track when we are in a diverging state, and we permit a value
of any type to be coerced **into** `!` if the expression that produced
it is diverging. This means that `fn foo() -> ! { panic!(); 22 }`
type-checks, even though the block has a type of `usize`.
Finally, coercions **from** the `!` type to any other are always
permitted.
Fixes#39808.
In master, this field was an arbitrary node-id (in fact, an id for
something that doesn't even exist in the HIR -- the `catch` node).
Breaks targeting this block used that id. In the newer system, this
field is a boolean, and any breaks targeted this block will use the
id of the block.
macros: improve `Span`'s expansion information
This PR improves `Span`'s expansion information. More specifically:
- It refactors AST node span construction to preserve expansion information.
- Today, we only use the underlying tokens' `BytePos`s, throwing away the `ExpnId`s.
- This improves the accuracy of AST nodes' expansion information, fixing #30506.
- It refactors `span.expn_id: ExpnId` to `span.ctxt: SyntaxContext` and removes `ExpnId`.
- This gives all tokens as much hygiene information as `Ident`s.
- This is groundwork for procedural macros 2.0 `TokenStream` API.
- This is also groundwork for declarative macros 2.0, which will need this hygiene information for some non-`Ident` tokens.
- It simplifies processing of spans' expansion information throughout the compiler.
- It fixes#40649.
- It fixes#39450 and fixes part of #23480.
r? @nrc
libcore: fix compilation on 16bit target (MSP430).
Since PR #40601 has been merged, libcore no longer compiles on MSP430.
The reason is this code in `break_patterns`:
```rust
let mut random = len;
random ^= random << 13;
random ^= random >> 17;
random ^= random << 5;
random &= modulus - 1;
```
It assumes that `len` is at least a 32 bit integer.
As a workaround replace `break_patterns` with an empty function for 16bit targets.
cc @stjepang
cc @alexcrichton
Clarify suggetion for field used as method
Instead of
```rust
error: no method named `src_addr` found for type `&wire::ipv4::Repr` in the current scope
--> src/wire/ipv4.rs:409:34
|
409 | packet.set_src_addr(self.src_addr());
| ^^^^^^^^
|
note: did you mean to write `self.src_addr`?
--> src/wire/ipv4.rs:409:34
|
409 | packet.set_src_addr(self.src_addr());
| ^^^^^^^^
```
present
```rust
error: no method named `src_addr` found for type `&wire::ipv4::Repr` in the current scope
--> src/wire/ipv4.rs:409:34
|
409 | packet.set_src_addr(self.src_addr());
| ^^^^^^^^ field, not a method
|
= help: did you mean to write `self.src_addr` instead of `self.src_addr(...)`?
```
Fix#38321.
Rustdoc: memoize `pub use`-reexported macros so they don't appear twice in docs
Closes#39436
Preserves existing behavior for `#[macro_reexport]`. `pub use`'d macros are shown as reexports unless inlined, and also correctly obey `#[doc(hidden)]`.
r? @jseyfried
cc @SergioBenitez
Attempt to cache git modules
Partial resolution of #40772, appveyor remains to be done once travis looks like it's working ok.
The approach in this PR is based on the `--reference` flag to `git-clone`/`git-submodule --update` and is a compromise based on the current limitations of the tools we're using.
The ideal would be:
1. have a cached pristine copy of rust-lang/rust master in `$HOME/rustsrc` with all submodules initialised
2. clone the PR branch with `git clone --recurse-submodules --reference $HOME/rustsrc git@github.com:rust-lang/rust.git`
This would (in the nonexistent ideal world) use the pristine copy as an object cache for the top level repo and all submodules, transferring over the network only the changes on the branch. Unfortunately, a) there is no way to manually control the initial clone with travis and b) even if there was, cloned submodules don't use the submodules of the reference as an object cache. So the steps we end up with are:
1. have a cached pristine copy of rust-lang/rust master in `$HOME/rustsrc` with all submodules initialised
2. have a cloned PR branch
3. extract the path of each submodule, and explicitly `git submodule update --init --reference $HOME/rustsrc/$module $module` (i.e. point directly to the location of the pristine submodule repo) for each one
I've also taken some care to make this forward compatible, both for adding and removing submodules.
r? @alexcrichton
We currently only emit a single call to the lifetime start intrinsic
for the personality slot alloca. This happens because we create that
call at the time that we create the alloca, instead of creating it each
time we start using it. Because LLVM usually removes the alloca before
the lifetime intrinsics are even considered, this didn't cause any
problems yet, but we should fix this anyway.
Now that we've also updated cargo's release process this commit also changes the
download location of Cargo from Cargos archives back to the static.r-l.o
archives. This should ensure that the Cargo download is the exact Cargo paired
with the rustc that we release.
borrowck: consolidate `mut` suggestions
This converts all of borrowck's `mut` suggestions to a new
`mc::ImmutabilityBlame` API instead of the current mix of various hacks.
Fixes#35937.
Fixes#40823.
Fixes#40859.
cc @estebank
r? @pnkfelix
Add all unstable features to Unstable Book.
Add all unstable features to the Unstable Book, also remove a few that
either no longer exist or were promoted to stable.
These changes were extracted out of
https://github.com/rust-lang/rust/pull/40694
Added core::cmp::Reverse for sort_by_key reverse sorting
I'm not sure if this is the best way to go about proposing this feature but it's pretty useful. It allows you to use `sort_by_key` and return tuples where a single item is then reversed to how it normally sorts.
I quite miss something like this in Rust currently though I'm not sure if this is the best way to implement it.
Add all unstable features to the Unstable Book, also remove a few that
either no longer exist or were promoted to stable.
These changes were extracted out of
https://github.com/rust-lang/rust/pull/40694
